1984 Mercury Fuel Problem

RogerK

Recruit
Joined
Jul 15, 2002
Messages
4
I just purchased the above mentioned outboard from a private party. The first time I took it out it stalled while trolling. It ran fine at WOT. It has pleanty of power when it runs and it starts great. I called the local dealer who is 75 miles away and the service managed told me to use Sea Foal to clean it out. (The Old Boy that sold it did so for health reasons and told me there was old gas in the tank.) I did the Sea Foam thing. Then it started stalling at WOT. It did it as I was heading to a fishing hole. On impulse I grabbed the priming ball and squeezed it a few times. The ball was soft, firmed up and the engine ran fine. For a few minutes then repeated. I took the cowling off so I could see the fuel filter. The engine is sucking fuel out of the filter faster than the fuel system is delivering. When the fuel level drops 1/4 to 1/3 down the fuel filter, the engine starts to lose power. Pumping the primer ball in the fuel line fills the fuel filter and I have full and smooth power.<br /><br />I've replaced the old fuel tank, so it isn't a plugged filter in the tank.<br /><br />I'm eyeballing the fuel line as the culprit.<br /><br />Question: Does this outboard have a fuel pump? Or should I look someplace else?<br /><br />It runs smooth and fine and fast as long as I give the primer a few pumps every so often. That is fairly consistent.<br /><br />I can repair any four stroke, ;) but the two cycle is a mystery. :confused: <br /><br />I forgot to add that it starts great.
 

akendall

Cadet
Joined
Jul 11, 2002
Messages
27
Re: 1984 Mercury Fuel Problem

I have the same problem with my Mercury 1986 115HP inline 6-cylinder (standard prop) when trying to pull waterskiers out of the water at full throttle - it stalls sometimes, but the problem is corrected when squeezing the primer bulb.<br /><br />A few suggestions I've had so far is as follows:<br />1. Bad check valve in primer bulb or air entering in fuel line at connectors - I checked this and it's ok<br />2. Fuel Pump needs replacement<br />3. Low end voltage stator needs replacement because I'm not getting the power needed in the low end torque (this is what the local marine mech suggested)<br />4. Clean out carbs - done but problem still persists
 
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